Euromonitor says more than $100bn will be spent on chocolate around the world in 2015 and almost $27bn will be spent on just chocolate bars in 2015 across the world, with milk chocolate being the firm favourite. It is by far the most popular in big markets such as the US, UK and Germany.

However, it is not the top choice in all countries.

A dark chocolate Lithuania Photograph: Mark Rice-Oxley/Guardian

More than 50% of the chocolate bars purchased in Israel and Iran are dark chocolate, while in Lithuania there was a 10.3% rise in sales in 2014-15.

As Jack Skelly, a food analyst at Euromonitor International points out, however, dark chocolate is also more expensive because of its higher cocoa content.

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“Milk chocolate is traditionally the most popular chocolate,” Skelly said. “In regions such as Asia Pacific, where the average person spends $3 (about £2) on chocolate a year - compared to around $57 in the US - dark chocolate is beyond the price point of many.”

Skelly says consumption of chocolate is stalling in western Europe and North America. Between 2010 and 2015, volume sales of chocolate declined by 2% in North America and 3% in the US “because it is difficult to get people to eat more chocolate than they already do”.

People becoming more health conscious of sugary and fatty products has also contributed to the change. But there have been other developments too. Over the same period, value sales increased in western Europe (2%) and in North America (4%) - “This partly suggests the west is indulging in buying higher quality chocolate, just less frequently than before. Indeed, we believe that sales of dark chocolate are growing.”

Premium brands such as Lindt (sales have increased by 65% over the past five years) as well as more niche brands are doing well says Euromonitor. “I think consumers are now beginning to expect higher quality products, and they’re willing to pay more for it,” said Skelly.